Note: Javascript is disabled or is not supported by your browser. For this reason, some items on this page will be unavailable. For more information about this message, please visit this page: About CDC.gov.

Search Links

Heading

Under a low magnification of only 50X, this photomicrograph revealed numbers of free-living, Naegleria gruberi amoebae, which had been cultured in an agar-filled Petri dish. Free-living amoebae belonging to the genera Acanthamoeba, Balamuthia, and Naegleria, are important causes of disease in humans and animals.

What is Naegleria?

Naegleria is an amoeba commonly found in the environment, in water and soil. Only one species of Naegleria has been found to infect humans, Naegleria fowleri.

How does infection with Naegleria occur?

Infection with Naegleria occurs when the amoeba enters the body through the nose while the person is swimming underwater, or diving. The amoebae then travel to the brain and spinal cord.

What are the signs and symptoms of Naegleria infection?

Infection with Naegleria causes the disease primary amebic meningoencephalitis, or PAM, a brain inflammation, which leads to the destruction of brain tissue. Initial signs and symptoms of PAM include headache, fever, nausea, vomiting, and stiff neck. The amoebae cause more extensive destruction of brain tissue, which leads to confusion, lack of attention to people and surroundings, loss of balance and bodily control, seizures, hallucinations. The disease progresses rapidly, and infection usually results in death within 3 to 7 days.

None - This image is in the public domain and thus free of any copyright restrictions. As a matter of courtesy we request that the content provider be credited and notified in any public or private usage of this image.